type I IUGR

Symmetrical intrauterine growth restriction is a type of intrauterine growth restriction (IUGR) where all fetal biometric parameters tend to be less than expected (below the 10 percentile) for the given gestational age. Both length and weight parameters are reduced.

Please, refer to the article on asymmetrical intrauterine growth restriction for a particular discussion of this other type of IUGR.

Pathology

As a general rule, fetuses with this type of IUGR pattern may present at an earlier stage in gestation compared with the asymmetrical IUGR pattern.

Etiology

• aneuploidic syndromes
  • triploidy
  • trisomy 13
  • trisomy 18
• infections, e.g. TORCH 
• other
  • topical use of maternal fluorinated glucocorticoid (rare)
  • external agents, e.g. nicotine, alcohol, heroin, ionizing radiation

Radiographic features

Antenatal ultrasound

All sonographic biometric parameters tend to be symmetrically reduced. Therefore, fetuses have normal or near normal:

• HC (head circumference) : AC (abdominal circumference) ratio
• FL (femoral length) : AC (abdominal circumference) ratio

Differential diagnosis

Differential considerations on ultrasound assessment include:

• incorrect dates
• lower end of normal variation, i.e. if parents are small

Siehe auch:

• Intrauterine Wachstumsretardierung
• asymmetrische intrauterine Wachstumsretardierung

und weiter:

• obstetric curriculum